Hello,
First of all, you have to remove processors from de original shared processor pool, but be sure you ca do that. If you have these processors assigned to LPARS, you can't remove it and you receive a this message

IF this happens, you have to change your LPAR config to choose other Shared Processor Pool. (se image below)

About processors in DefaultPool, you can use it, but , of course, you have to choose in each LPAR which Pool you want and also you have to control your licenses.
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Eduard Marco Galindo
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